Antlr4.Parse.ScopeParser._SplitArgumentList C# (CSharp) Method

        public static int _SplitArgumentList(string actionText,
                                             int start,
                                             int targetChar,
                                             int separatorChar,
                                             IList<System.Tuple<string, int>> args)
        {
            if (actionText == null)
            {
                return -1;
            }

            actionText = Regex.Replace(actionText, "//[^\\n]*", "");
            int n = actionText.Length;
            //System.Console.WriteLine("actionText@" + start + "->" + (char)targetChar + "=" + actionText.Substring(start, n - start));
            int p = start;
            int last = p;
            while (p < n && actionText[p] != targetChar)
            {
                int c = actionText[p];
                switch (c)
                {
                case '\'':
                    p++;
                    while (p < n && actionText[p] != '\'')
                    {
                        if (actionText[p] == '\\' && (p + 1) < n &&
                             actionText[p + 1] == '\'')
                        {
                            p++; // skip escaped quote
                        }
                        p++;
                    }
                    p++;
                    break;
                case '"':
                    p++;
                    while (p < n && actionText[p] != '\"')
                    {
                        if (actionText[p] == '\\' && (p + 1) < n &&
                             actionText[p + 1] == '\"')
                        {
                            p++; // skip escaped quote
                        }
                        p++;
                    }
                    p++;
                    break;
                case '(':
                    p = _SplitArgumentList(actionText, p + 1, ')', separatorChar, args);
                    break;
                case '{':
                    p = _SplitArgumentList(actionText, p + 1, '}', separatorChar, args);
                    break;
                case '<':
                    if (actionText.IndexOf('>', p + 1) >= p)
                    {
                        // do we see a matching '>' ahead?  if so, hope it's a generic
                        // and not less followed by expr with greater than
                        p = _SplitArgumentList(actionText, p + 1, '>', separatorChar, args);
                    }
                    else
                    {
                        p++; // treat as normal char
                    }
                    break;
                case '[':
                    p = _SplitArgumentList(actionText, p + 1, ']', separatorChar, args);
                    break;
                default:
                    if (c == separatorChar && targetChar == -1)
                    {
                        string arg = actionText.Substring(last, p - last);
                        int index = last;
                        while (index < p && char.IsWhiteSpace(actionText[index]))
                        {
                            index++;
                        }
                        //System.out.println("arg="+arg);
                        args.Add(Tuple.Create(arg.Trim(), index));
                        last = p + 1;
                    }
                    p++;
                    break;
                }
            }
            if (targetChar == -1 && p <= n)
            {
                string arg = actionText.Substring(last, p - last).Trim();
                int index = last;
                while (index < p && char.IsWhiteSpace(actionText[index]))
                {
                    index++;
                }
                //System.out.println("arg="+arg);
                if (arg.Length > 0)
                {
                    args.Add(Tuple.Create(arg.Trim(), index));
                }
            }
            p++;
            return p;
        }